In U.S. Pat. Nos. 3,773,925 and 3,780,173, there are described and claimed, respectively, a new polyene antibiotic (partricin) and its methyl ester and the preparations thereof, both of which have a marked anti-infective activity on protozoa and pathogenic fungi in mammals and plants. Such activity has shown to be of particular value in treating infections caused by Trichomonas vaginalis and/or Candida albicans in humans. For reasons of toxicity, which are not separate from those of activity, in human pathology, the methyl ester of partricin, which is known as mepartricin (USAN) is currently used; other alkyl esters of partricin which have been prepared include the ethyl, propyl and butyl esters, as well as the alkyl esters of N-mono and disubstituted partricin, such as diacetyl partricin, dipropionyl partricin, dibutyryl partricin and disuccinyl partricin, which, together with the preparation thereof, are described and claimed in U.S. Pat. No. 3,961,047 and in pending U.S. Patent Application No. 839,509 filed the 4th October, 1977. Furthermore, water-soluble complexes of partricin and of alkyl esters thereof have been disclosed in U.S. Pat. Nos. 3,961,048 and 4,017,603.
The active compounds contemplated in the present invention include partricin, C.sub.1 -C.sub.6 esters of partricin and C.sub.1 -C.sub.6 esters of N-mono- and disubstituted partricin wherein the N-substituents are C.sub.1 -C.sub.6 alkyl or C.sub.1 -C.sub.6 carboxylic acyl.
From a biological point of view, these derivatives have also shown particular activity against protozoa and pathogenic fungi.